The present invention relates to tamper-proof container closures and, more particularly, to a tamper-proof container closure cap with a self-removing ring.
Tamper-proof container closures are widely used, particularly in the dairy industry, to demonstrate to the final consumer that the contents of a container have not been contaminated or adulterated subsequent to bottling. One type of tamper-proof container closure employs a separable ring member having a plurality of triangular pawls to prevent such tampering. The ring is coupled to the cap by frangible elements located at discrete points around the cap. When the cap is twisted open, the pawls of the ring lock into engagement with corresponding teeth on the container, breaking the frangible elements, and separating the ring from the cap. Such closures are described in greater detail in U.S. Pat. No. 3,874,540 issued to W. E. Hidding; U.S. Pat. No. 3,504,818 issued to H. Crisci et al.; and U.S. Pat. No. 3,249,247 issued to P. H. Babiol.
One problem with these types of closures is proper disposition of the ring after separation. If the ring is secured to the container, it remains as an unsightly toothed structure permitting the collection of dirt and bacteria in tiny corners. If the ring is not secured to the container, it will either fall off during pouring from the container or it must be removed manually. Manual removal, which is usually effected after the cap is twisted off, almost inevitably results in unsanitary manual contact with the mouth of the container.
In an attempt to overcome the problem of ring disposition, the industry has begun to provide the rings with handles so that they may be manually torn from the container and cap prior to removing the cap. Such handles, however are typically small molded structures readily subject to premature breakage. Moreover, the handles are typically secured to the ring by one or more frangible connections which must be manually broken before the handle can be pulled to tear the ring away.